[issue:221] babel-french: footnote incompatibility

[Hironobu Yamashita]

Hi Daniel,

A Japanese user reported the following issue:
the footnote layout changed between TeX Live 2016 and TeX Live 2018.
MWE is shown at the end of this mail, and resulting PDFs attached.

My friend and I looked into french.ldf, and found that the culprit is
\begingroup ... \endgroup in the definition of \@makefntext.

I guess the grouping is meant for localizing tokens in \localleftbox,
which is a primitive specific to LuaTeX (and Omega/Aleph).
Therefore, the grouping here is no more harm than good, at least
for pdfLaTeX, XeLaTeX and Japanese pLaTeX/upLaTeX.
I don't know what is a best practice for LuaLaTeX.

% =========
%#!pdflatex
\documentclass{article}
%%% suppose that a document class redefines \@makefntext
\makeatletter
\def\@makefntext#1{%
  \advance\leftskip 15pt
  \parindent 3pt
  \noindent
  \llap{\@makefnmark\hskip1pt}#1}
\makeatother
%%%
\usepackage[french,english]{babel}
\usepackage{lipsum}
\begin{document}
\lipsum*[1]%
\footnote{\lipsum*[2]}%
\lipsum*[3]
\end{document}
% =========


p.s. Providing a fallback definition of \localleftbox (= silently
gobbles the following argument) may be also problematic, but
that's another issue...


Best regards,

Hironobu Yamashita

GitHub: https://github.com/aminophen
Japanese TeX Development Community (https://texjp.org)

-------------- next part --------------
テキスト形式以外の添付ファイルを保管しました...
ファイル名: babelfrench-tl2018.pdf
型:         application/pdf
サイズ:     11270 バイト
説明:       無し
URL:        <http://ml.texjp.org/pipermail/issue/attachments/20180913/f0f8df0b/attachment.pdf>

-------------- next part --------------
テキスト形式以外の添付ファイルを保管しました...
ファイル名: babelfrench-tl2016.pdf
型:         application/pdf
サイズ:     11270 バイト
説明:       無し
URL:        <http://ml.texjp.org/pipermail/issue/attachments/20180913/f0f8df0b/attachment-0001.pdf>